Radiation therapy has been employed to treat tumorous tissue. In radiation therapy, a high energy beam is applied from an external source towards the patient. The external source, which may be rotating (as in the case for arc therapy), produces a collimated beam of radiation that is directed into the patient to the target site. The dose and placement of the dose must be accurately controlled to ensure that the tumor receives sufficient radiation, and that damage to the surrounding healthy tissue is minimized.
Generally, a radiation treatment plan is determined before the radiation therapy is performed. During a radiation planning session, radiation treatment planning is performed before treatment radiation is delivered to a patient. This allows an accurate and precise dosage of radiation to be delivered to a patient.
In a typical radiotherapy treatment planning process, clinicians identify the target region (e.g., tumor) and critical organs from a three-dimensional image (e.g., CT image) of the patient, and manually segment the tumor (to receive a prescribed dose of radiation) and critical organs that are at risk of damage from the radiation treatment. Although there are guidelines that govern the entire planning process, each patient is different from the last, and therefore, each planning process is customized. The variability between patient anatomy, image quality, and tissue response to radiation means that it has not been possible to reliably automate the planning process, making treatment planning a time consuming process.